From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 30D3F4C6A for ; Mon, 14 Nov 2022 13:02:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A793BC433D7; Mon, 14 Nov 2022 13:02:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1668430968; bh=2vrB+AmVXaTgR2HF5rocIYf46Z1wLog3CHmE1zgG6X0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DIaEyn9YX4vDWeGE09xJuDkvvGFyGCKCXEzKjgPdZ0b9kVkWnaJNZnrbzWkhemgAq SOr8OqmvJR18jzv8+qRP5LbugDKuX0kHzMan5kumXUnRIXDyPyCfZbqrK5bwer6G5d G7DW3eEx8zWtMKlxjZjByETe+zZKL4nCX0quyZ9Q= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yuan Can , Maxime Ripard , Sasha Levin Subject: [PATCH 6.0 052/190] drm/vc4: Fix missing platform_unregister_drivers() call in vc4_drm_register() Date: Mon, 14 Nov 2022 13:44:36 +0100 Message-Id: <20221114124501.061603924@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221114124458.806324402@linuxfoundation.org> References: <20221114124458.806324402@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Yuan Can [ Upstream commit cf53db768a8790fdaae2fa3a81322b080285f7e5 ] A problem about modprobe vc4 failed is triggered with the following log given: [ 420.327987] Error: Driver 'vc4_hvs' is already registered, aborting... [ 420.333904] failed to register platform driver vc4_hvs_driver [vc4]: -16 modprobe: ERROR: could not insert 'vc4': Device or resource busy The reason is that vc4_drm_register() returns platform_driver_register() directly without checking its return value, if platform_driver_register() fails, it returns without unregistering all the vc4 drivers, resulting the vc4 can never be installed later. A simple call graph is shown as below: vc4_drm_register() platform_register_drivers() # all vc4 drivers are registered platform_driver_register() driver_register() bus_add_driver() priv = kzalloc(...) # OOM happened # return without unregister drivers Fixing this problem by checking the return value of platform_driver_register() and do platform_unregister_drivers() if error happened. Fixes: c8b75bca92cb ("drm/vc4: Add KMS support for Raspberry Pi.") Signed-off-by: Yuan Can Signed-off-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20221103014705.109322-1-yuancan@huawei.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/vc4/vc4_drv.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c index c186ace7f83b..2064863a0fd3 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.c +++ b/drivers/gpu/drm/vc4/vc4_drv.c @@ -476,7 +476,12 @@ static int __init vc4_drm_register(void) if (ret) return ret; - return platform_driver_register(&vc4_platform_driver); + ret = platform_driver_register(&vc4_platform_driver); + if (ret) + platform_unregister_drivers(component_drivers, + ARRAY_SIZE(component_drivers)); + + return ret; } static void __exit vc4_drm_unregister(void) -- 2.35.1